src/login/eloginctl.c

   1 /***
   2   This file is part of elogind.
   3
   4   Copyright 2017 Sven Eden
   5
   6   elogind is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as published by
   8   the Free Software Foundation; either version 2.1 of the License, or
   9   (at your option) any later version.
  10
  11   elogind is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with elogind; If not, see <http://www.gnu.org/licenses/>.
  18 ***/
  19
  20
  21 #include "bus-error.h"
  22 #include "bus-util.h"
  23 #include "eloginctl.h"
  24 #include "logind-action.h"
  25 #include "parse-util.h"
  26 #include "process-util.h"
  27 #include "sd-login.h"
  28 #include "sd-messages.h"
  29 #include "spawn-polkit-agent.h"
  30 #include "string-util.h"
  31 #include "strv.h"
  32 #include "terminal-util.h"
  33 #include "user-util.h"
  34 #include "virt.h"
  35
  36
  37 elogind_action arg_action            = _ACTION_INVALID;
  38 bool           arg_ask_password      = true;
  39 bool           arg_ignore_inhibitors = false;
  40 bool           arg_no_wall           = false;
  41 BusTransport   arg_transport         = BUS_TRANSPORT_LOCAL;
  42 char**         arg_wall              = NULL;
  43 usec_t         arg_when              = 0;
  44
  45 static const struct {
  46         HandleAction action;
  47         const char*  verb;
  48 } action_table[_ACTION_MAX] = {
  49         [ACTION_POWEROFF]     = { HANDLE_POWEROFF,     "poweroff",    },
  50         [ACTION_REBOOT]       = { HANDLE_REBOOT,       "reboot",      },
  51         [ACTION_SUSPEND]      = { HANDLE_SUSPEND,      "suspend",     },
  52         [ACTION_HIBERNATE]    = { HANDLE_HIBERNATE,    "hibernate",   },
  53         [ACTION_HYBRID_SLEEP] = { HANDLE_HYBRID_SLEEP, "hybrid-sleep" },
  54 };
  55
  56 static int elogind_set_wall_message(sd_bus* bus, const char* msg);
  57
  58 static enum elogind_action verb_to_action(const char *verb) {
  59         enum elogind_action i;
  60
  61         for (i = _ACTION_INVALID; i < _ACTION_MAX; i++)
  62                 if (streq_ptr(action_table[i].verb, verb))
  63                         return i;
  64
  65         return _ACTION_INVALID;
  66 }
  67
  68 static int check_inhibitors(sd_bus* bus, enum elogind_action a) {
  69         _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
  70         _cleanup_strv_free_ char **sessions = NULL;
  71         const char *what, *who, *why, *mode;
  72         uint32_t uid, pid;
  73         unsigned c = 0;
  74         char **s;
  75         int r;
  76
  77         if (arg_ignore_inhibitors)
  78                 return 0;
  79
  80         if (arg_when > 0)
  81                 return 0;
  82
  83         if (geteuid() == 0)
  84                 return 0;
  85
  86         if (!on_tty())
  87                 return 0;
  88
  89         r = sd_bus_call_method(
  90                         bus,
  91                         "org.freedesktop.login1",
  92                         "/org/freedesktop/login1",
  93                         "org.freedesktop.login1.Manager",
  94                         "ListInhibitors",
  95                         NULL,
  96                         &reply,
  97                         NULL);
  98         if (r < 0)
  99                 /* If logind is not around, then there are no inhibitors... */
 100                 return 0;
 101
 102         r = sd_bus_message_enter_container(reply, SD_BUS_TYPE_ARRAY, "(ssssuu)");
 103         if (r < 0)
 104                 return bus_log_parse_error(r);
 105
 106         while ((r = sd_bus_message_read(reply, "(ssssuu)", &what, &who, &why, &mode, &uid, &pid)) > 0) {
 107                 _cleanup_free_ char *comm = NULL, *user = NULL;
 108                 _cleanup_strv_free_ char **sv = NULL;
 109
 110                 if (!streq(mode, "block"))
 111                         continue;
 112
 113                 sv = strv_split(what, ":");
 114                 if (!sv)
 115                         return log_oom();
 116
 117                 if ((pid_t) pid < 0)
 118                         return log_error_errno(ERANGE, "Bad PID %"PRIu32": %m", pid);
 119
 120                 if (!strv_contains(sv,
 121                                    IN_SET(a,
 122                                           ACTION_HALT,
 123                                           ACTION_POWEROFF,
 124                                           ACTION_REBOOT,
 125                                           ACTION_KEXEC) ? "shutdown" : "sleep"))
 126                         continue;
 127
 128                 get_process_comm(pid, &comm);
 129                 user = uid_to_name(uid);
 130
 131                 log_warning("Operation inhibited by \"%s\" (PID "PID_FMT" \"%s\", user %s), reason is \"%s\".",
 132                             who, (pid_t) pid, strna(comm), strna(user), why);
 133
 134                 c++;
 135         }
 136         if (r < 0)
 137                 return bus_log_parse_error(r);
 138
 139         r = sd_bus_message_exit_container(reply);
 140         if (r < 0)
 141                 return bus_log_parse_error(r);
 142
 143         /* Check for current sessions */
 144         sd_get_sessions(&sessions);
 145         STRV_FOREACH(s, sessions) {
 146                 _cleanup_free_ char *type = NULL, *tty = NULL, *seat = NULL, *user = NULL, *service = NULL, *class = NULL;
 147
 148                 if (sd_session_get_uid(*s, &uid) < 0 || uid == getuid())
 149                         continue;
 150
 151                 if (sd_session_get_class(*s, &class) < 0 || !streq(class, "user"))
 152                         continue;
 153
 154                 if (sd_session_get_type(*s, &type) < 0 || (!streq(type, "x11") && !streq(type, "tty")))
 155                         continue;
 156
 157                 sd_session_get_tty(*s, &tty);
 158                 sd_session_get_seat(*s, &seat);
 159                 sd_session_get_service(*s, &service);
 160                 user = uid_to_name(uid);
 161
 162                 log_warning("User %s is logged in on %s.", strna(user), isempty(tty) ? (isempty(seat) ? strna(service) : seat) : tty);
 163                 c++;
 164         }
 165
 166         if (c <= 0)
 167                 return 0;
 168
 169         log_error("Please retry operation after closing inhibitors and logging out other users.\nAlternatively, ignore inhibitors and users with 'loginctl -i %s'.",
 170                   action_table[a].verb);
 171
 172         return -EPERM;
 173 }
 174
 175 int elogind_cancel_shutdown(sd_bus *bus) {
 176         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 177         int r;
 178
 179         r = elogind_set_wall_message(bus, NULL);
 180
 181         if (r < 0) {
 182                 log_warning_errno(r, "Failed to set wall message, ignoring: %s",
 183                                   bus_error_message(&error, r));
 184                 sd_bus_error_free(&error);
 185         }
 186
 187         r = sd_bus_call_method(
 188                         bus,
 189                         "org.freedesktop.login1",
 190                         "/org/freedesktop/login1",
 191                         "org.freedesktop.login1.Manager",
 192                         "CancelScheduledShutdown",
 193                         &error,
 194                         NULL, NULL);
 195         if (r < 0)
 196                 return log_warning_errno(r, "Failed to talk to elogind, shutdown hasn't been cancelled: %s", bus_error_message(&error, r));
 197
 198         return 0;
 199 }
 200
 201 void elogind_cleanup(void) {
 202         polkit_agent_close();
 203         strv_free(arg_wall);
 204 }
 205
 206 static void elogind_log_special(enum elogind_action a) {
 207 #ifdef ENABLE_DEBUG_ELOGIND
 208         switch (a) {
 209         case ACTION_HALT:
 210                 log_struct(LOG_INFO,
 211                            LOG_MESSAGE("Halt action called."),
 212                            LOG_MESSAGE_ID(SD_MESSAGE_SHUTDOWN),
 213                            NULL);
 214                 break;
 215         case ACTION_POWEROFF:
 216                 log_struct(LOG_INFO,
 217                            LOG_MESSAGE("Poweroff action called."),
 218                            LOG_MESSAGE_ID(SD_MESSAGE_SHUTDOWN),
 219                            NULL);
 220                 break;
 221         case ACTION_REBOOT:
 222                 log_struct(LOG_INFO,
 223                            LOG_MESSAGE("Reboot action called."),
 224                            LOG_MESSAGE_ID(SD_MESSAGE_SHUTDOWN),
 225                            NULL);
 226                 break;
 227         case ACTION_KEXEC:
 228                 log_struct(LOG_INFO,
 229                            LOG_MESSAGE("KExec action called."),
 230                            LOG_MESSAGE_ID(SD_MESSAGE_SHUTDOWN),
 231                            NULL);
 232                 break;
 233         case ACTION_SUSPEND:
 234                 log_struct(LOG_INFO,
 235                            LOG_MESSAGE("Suspend action called."),
 236                            LOG_MESSAGE_ID(SD_MESSAGE_SLEEP_START),
 237                            NULL);
 238                 break;
 239         case ACTION_HIBERNATE:
 240                 log_struct(LOG_INFO,
 241                            LOG_MESSAGE("Hibernate action called."),
 242                            LOG_MESSAGE_ID(SD_MESSAGE_SLEEP_START),
 243                            NULL);
 244         case ACTION_HYBRID_SLEEP:
 245                 log_struct(LOG_INFO,
 246                            LOG_MESSAGE("Hybrid-Sleep action called."),
 247                            LOG_MESSAGE_ID(SD_MESSAGE_SLEEP_START),
 248                            NULL);
 249         case ACTION_CANCEL_SHUTDOWN:
 250                 log_struct(LOG_INFO,
 251                            LOG_MESSAGE("Cancel Shutdown called."),
 252                            LOG_MESSAGE_ID(SD_MESSAGE_SHUTDOWN),
 253                            NULL);
 254                 break;
 255         default:
 256                 break;
 257         }
 258 #endif // ENABLE_DEBUG_ELOGIND
 259 }
 260
 261 static int elogind_reboot(sd_bus *bus, enum elogind_action a) {
 262         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 263         const char *method  = NULL;
 264         int r;
 265         static const char *table[_ACTION_MAX] = {
 266                 [ACTION_REBOOT]          = "The system is going down for reboot NOW!",
 267                 [ACTION_POWEROFF]        = "The system is going down for power-off NOW!"
 268         };
 269
 270         if (!bus)
 271                 return -EIO;
 272
 273         switch (a) {
 274
 275         case ACTION_POWEROFF:
 276                 method = "PowerOff";
 277                 break;
 278
 279         case ACTION_REBOOT:
 280                 method = "Reboot";
 281                 break;
 282
 283         case ACTION_SUSPEND:
 284                 method = "Suspend";
 285                 break;
 286
 287         case ACTION_HIBERNATE:
 288                 method = "Hibernate";
 289                 break;
 290
 291         case ACTION_HYBRID_SLEEP:
 292                 method = "HybridSleep";
 293                 break;
 294
 295         default:
 296                 return -EINVAL;
 297         }
 298
 299         polkit_agent_open_if_enabled();
 300         r = elogind_set_wall_message(bus, table[a]);
 301
 302         if (r < 0) {
 303                 log_warning_errno(r, "Failed to set wall message, ignoring: %s",
 304                                   bus_error_message(&error, r));
 305                 sd_bus_error_free(&error);
 306         }
 307
 308         /* Now call elogind itself to request the operation */
 309         r = sd_bus_call_method(
 310                         bus,
 311                         "org.freedesktop.login1",
 312                         "/org/freedesktop/login1",
 313                         "org.freedesktop.login1.Manager",
 314                         method,
 315                         &error,
 316                         NULL,
 317                         "b", arg_ask_password);
 318
 319         if (r < 0)
 320                 log_error("Failed to execute operation: %s", bus_error_message(&error, r));
 321
 322         return r;
 323 }
 324
 325 static int elogind_schedule_shutdown(sd_bus *bus, enum elogind_action a) {
 326         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 327         const char *method  = NULL;
 328         int r;
 329
 330         if (!bus)
 331                 return -EIO;
 332
 333         switch (a) {
 334
 335         case ACTION_POWEROFF:
 336                 method = "poweroff";
 337                 break;
 338
 339         case ACTION_REBOOT:
 340                 method = "reboot";
 341                 break;
 342
 343         default:
 344                 return -EINVAL;
 345         }
 346
 347         r = elogind_set_wall_message(bus, NULL);
 348
 349         if (r < 0) {
 350                 log_warning_errno(r, "Failed to set wall message, ignoring: %s",
 351                                   bus_error_message(&error, r));
 352                 sd_bus_error_free(&error);
 353         }
 354
 355         r = sd_bus_call_method(
 356                         bus,
 357                         "org.freedesktop.login1",
 358                         "/org/freedesktop/login1",
 359                         "org.freedesktop.login1.Manager",
 360                         "ScheduleShutdown",
 361                         &error,
 362                         NULL,
 363                         "st",
 364                         method,
 365                         arg_when);
 366
 367         if (r < 0)
 368                 log_error("Failed to execute operation: %s", bus_error_message(&error, r));
 369
 370         return r;
 371 }
 372
 373 static int elogind_set_wall_message(sd_bus* bus, const char* msg) {
 374         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 375         _cleanup_free_ char *m = NULL;
 376         int r;
 377
 378         if (strv_extend(&arg_wall, msg) < 0)
 379                 return log_oom();
 380
 381         m = strv_join(arg_wall, " ");
 382         if (!m)
 383                 return log_oom();
 384
 385         r = sd_bus_call_method(
 386                         bus,
 387                         "org.freedesktop.login1",
 388                         "/org/freedesktop/login1",
 389                         "org.freedesktop.login1.Manager",
 390                         "SetWallMessage",
 391                         &error,
 392                         NULL,
 393                         "sb",
 394                         m,
 395                         !arg_no_wall);
 396
 397         if (r < 0)
 398                 return log_warning_errno(r, "Failed to set wall message, ignoring: %s", bus_error_message(&error, r));
 399
 400         return 0;
 401 }
 402
 403 static int parse_shutdown_time_spec(const char *t, usec_t *_u) {
 404         assert(t);
 405         assert(_u);
 406
 407         if (streq(t, "now"))
 408                 *_u = 0;
 409         else if (!strchr(t, ':')) {
 410                 uint64_t u;
 411
 412                 if (safe_atou64(t, &u) < 0)
 413                         return -EINVAL;
 414
 415                 *_u = now(CLOCK_REALTIME) + USEC_PER_MINUTE * u;
 416         } else {
 417                 char *e = NULL;
 418                 long hour, minute;
 419                 struct tm tm = {};
 420                 time_t s;
 421                 usec_t n;
 422
 423                 errno = 0;
 424                 hour = strtol(t, &e, 10);
 425                 if (errno > 0 || *e != ':' || hour < 0 || hour > 23)
 426                         return -EINVAL;
 427
 428                 minute = strtol(e+1, &e, 10);
 429                 if (errno > 0 || *e != 0 || minute < 0 || minute > 59)
 430                         return -EINVAL;
 431
 432                 n = now(CLOCK_REALTIME);
 433                 s = (time_t) (n / USEC_PER_SEC);
 434
 435                 assert_se(localtime_r(&s, &tm));
 436
 437                 tm.tm_hour = (int) hour;
 438                 tm.tm_min = (int) minute;
 439                 tm.tm_sec = 0;
 440
 441                 assert_se(s = mktime(&tm));
 442
 443                 *_u = (usec_t) s * USEC_PER_SEC;
 444
 445                 while (*_u <= n)
 446                         *_u += USEC_PER_DAY;
 447         }
 448
 449         return 0;
 450 }
 451
 452 void polkit_agent_open_if_enabled(void) {
 453
 454         /* Open the polkit agent as a child process if necessary */
 455
 456         if (!arg_ask_password)
 457                 return;
 458
 459         if (arg_transport != BUS_TRANSPORT_LOCAL)
 460                 return;
 461
 462         polkit_agent_open();
 463 }
 464
 465 int start_special(int argc, char *argv[], void *userdata) {
 466         sd_bus *bus = userdata;
 467         enum elogind_action a;
 468         int r;
 469         char** wall = NULL;
 470
 471         assert(argv);
 472
 473         a = verb_to_action(argv[0]);
 474
 475         elogind_log_special(a);
 476
 477         /* No power off actions in chroot environments */
 478         if ( IN_SET(a, ACTION_POWEROFF, ACTION_REBOOT)
 479           && (running_in_chroot() > 0) ) {
 480                 log_info("Running in chroot, ignoring request.");
 481                 return 0;
 482         }
 483
 484         /* Check time arguments */
 485         if ( IN_SET(a, ACTION_POWEROFF, ACTION_REBOOT)
 486           && (argc > 1)
 487           && (arg_action != ACTION_CANCEL_SHUTDOWN) ) {
 488                 r = parse_shutdown_time_spec(argv[1], &arg_when);
 489                 if (r < 0) {
 490                         log_error("Failed to parse time specification: %s", argv[optind]);
 491                         return r;
 492                 }
 493         } else
 494                 arg_when = now(CLOCK_REALTIME) + USEC_PER_MINUTE;
 495
 496         /* The optional user wall message must be set */
 497         if ((argc > 1) && (arg_action == ACTION_CANCEL_SHUTDOWN) )
 498                 /* No time argument for shutdown cancel */
 499                 wall = argv + 1;
 500         else if (argc > 2)
 501                 /* We skip the time argument */
 502                 wall = argv + 2;
 503
 504         if (wall) {
 505                 arg_wall = strv_copy(wall);
 506                 if (!arg_wall)
 507                         return log_oom();
 508         }
 509
 510         /* Switch to cancel shutdown, if a shutdown action was requested,
 511            and the option to cancel it was set: */
 512         if ( IN_SET(a, ACTION_POWEROFF, ACTION_REBOOT)
 513           && (arg_action == ACTION_CANCEL_SHUTDOWN) )
 514                 return elogind_cancel_shutdown(bus);
 515
 516         r = check_inhibitors(bus, a);
 517         if (r < 0)
 518                 return r;
 519
 520         /* Perform requested action */
 521         if (IN_SET(a,
 522                    ACTION_POWEROFF,
 523                    ACTION_REBOOT,
 524                    ACTION_SUSPEND,
 525                    ACTION_HIBERNATE,
 526                    ACTION_HYBRID_SLEEP)) {
 527                 if (arg_when > 0)
 528                         return elogind_schedule_shutdown(bus, a);
 529                 else
 530                         return elogind_reboot(bus, a);
 531         }
 532
 533         return -EOPNOTSUPP;
 534 }
 535